Handle schema names in table metadata

[greg0ire]

Fixes #1566

In a previous commit, I switched from introspectTable(), which handles this with a single argument to introspectTableByUnquotedName(), which handles it with 2 arguments.

I could not find a way to test this since we use SQLite and that the corresponding DBAL platform does not support schemas.

[SenseException]

It looks like there's no test that covers table names with a dot. Maybe you can cover your new code path with a test like Doctrine\Migrations\Tests\Metadata\Storage\TableMetadataStorageTest::testTableStructure()

[greg0ire]

@SenseException that test relies on SQLite, which does not support namespaces.

[stlrnz]

I can confirm that this PR fixes #1566

Thank you!

[SenseException]

@greg0ire It introduces a new code path with a new if-block, that I, AFAIK, don't see covered by a test. Please let me know if there's one that covers the new path elsewhere that I missed.

[greg0ire]

I don't think it is currently covered because it is about schemas, and we only have SQLite available in this test suite I think, and it does not support schemas, or rather, the corresponding DBAL platform doesn't.